1. Field of the Invention
The present invention relates to mainframe computer systems and more particularly to CICS transaction routine on mainframe computing systems.
2. Description of the Related Art
CICS is an acronym referring a transaction server that executes primarily in a mainframe computing system environment. CICS is designed for rapid, high-volume processing of computing transactions. The computing transactions can be included as part of a transaction oriented application, which in turn can be developed using a variety of programming languages. The programming languages, in turn, can use CICS-supplied language extensions to interact with CICS resources such as files, database connections, or to invoke functions such as web services.
Generally, a CICS transaction is a set of operations that perform a task together. Usually, the majority of transactions are relatively simple tasks such as requesting an inventory list or entering a debit or credit to an account. Remarkably, CICS supports thousands of transactions per second. Of note, usually CICS refers not only to a CICS Transaction Server, but also to a portfolio of transaction servers, connectors, referred to as CICS transaction gateways, and a number of supporting CICS tools.
In a typical mainframe computing environment, a CICS installation includes one or more regions, each generally referred to as a CICS region, spread across one or more operating system images. Within the mainframe computing environment, CICS transactions are routed from one CICS region to another, quite often with one routing region in the first instance leading to an Application Owning Region (AOR) or Terminal Owning Region (TOR). The CICS transactions can in turn feed to other CICS systems in a continuous chain.
Whenever a CICS transaction is routed from one region to another, resources remain allocated on the routed-from region despite the request being handled within a different, routed-to region. Thus, resources can be wasted within the routed-from region. To the extent, then, that a typical CICS installation consists of a number of distinct applications, each application having its own TOR and one or more AORs, and given the number transactions processing each second, the waste can be substantial.